CN110352356B

CN110352356B - Shunt resistor and current detection device using same

Info

Publication number: CN110352356B
Application number: CN201880010422.3A
Authority: CN
Inventors: 远藤保
Original assignee: Koa Corp
Current assignee: Koa Corp
Priority date: 2017-02-15
Filing date: 2018-01-31
Publication date: 2022-03-04
Anticipated expiration: 2038-01-31
Also published as: JP2018132422A; DE112018000871T5; CN110352356A; JP6854143B2; WO2018150870A1; US11187725B2; US20200025802A1

Abstract

A shunt resistor, comprising: a first terminal and a second terminal made of a conductive metal material; and the resistor is arranged between the first terminal and the second terminal, wherein through holes are respectively formed on the first terminal and the second terminal, and a convex structure is arranged on the side, opposite to the joint of the resistor, of at least one of the first terminal and the second terminal.

Description

Shunt resistor and current detection device using same

Technical Field

The present invention relates to a shunt resistor and a current detection device using the shunt resistor.

Background

The shunt resistor is used, for example, to detect a current in a semiconductor power module or the like mounted on an electric vehicle.

The relevant prior art documents for shunt resistors used for this purpose are as follows:

patent document 1 listed below discloses a structure in which stud-shaped electrodes of shunt resistors are inserted into bus bar (current terminal row) insertion holes first, and then fastened with nuts.

Patent document 2 listed below discloses a structure in which a washer-shaped shunt resistor is inserted through a battery terminal and fixed.

Documents of the prior art

Patent document

Patent document 1: japanese patent application publication No. JP2012-109474

Patent document 2: japanese patent application publication No. JP2008-047571

Disclosure of Invention

Problems to be solved by the invention

The shunt resistor described in patent document 1 has a problem that the electrode is complicated to manufacture and mount.

The shunt resistor described in the above patent document 2 has a problem that the resistance value of the resistor is difficult to control.

Further, each of the above documents does not disclose a specific mounting method of the shunt resistor on the wiring board.

The invention aims to provide a shunt resistor and a current detection device using the shunt resistor, which can be mounted on a circuit board, have simple mounting mode, do not need overlarge mounting space and can realize high-precision current detection.

Means for solving the problems

According to an aspect of the present invention, there is provided a shunt resistor including: a first terminal and a second terminal made of a conductive metal material; and a resistor arranged between the first terminal and the second terminal, wherein through holes are respectively formed on the first terminal and the second terminal, and at least one of the first terminal and the second terminal is provided with a convex structure on the side opposite to the joint of the resistor.

Preferably, the resistor is a plurality of resistors, and the resistors are connected in parallel between the first terminal and the second terminal.

Preferably, the resistor is disposed around the via.

In addition, the present invention also provides a current detection device including: a first wiring structure and a second wiring structure forming a current path; a housing containing the second wiring structure; a circuit board; and a shunt resistor shorting the first and second wiring structures, the shunt resistor including: a first terminal and a second terminal made of a conductive metal material; and a resistor provided between the first terminal and the second terminal, wherein a first via hole and a second via hole are formed on the first terminal and the second terminal, respectively, and in the shunt resistor: the first terminal is connected with the first wiring structure; the second terminal is connected with the second wiring structure through a third through hole formed in the circuit board; the shunt resistor and the second wiring structure are fixed by fixing members inserted into the first through hole and the second through hole.

Preferably, the second terminal has a protrusion structure formed thereon, and the protrusion structure is received in the third through hole.

Preferably, the second terminal is pressed against a part around the third through hole of the circuit board.

The present specification contains the disclosure of japanese patent application No. JP2017-026361, which is the basis of the priority of the present application.

Effects of the invention

The shunt resistor and the current detection device using the shunt resistor are simple and convenient in installation mode on the circuit board, do not need overlarge installation space, and can realize high-precision current detection.

Drawings

Fig. 1 is a perspective view showing an exemplary structure of a shunt resistor according to a first embodiment of the present invention, in which fig. 1(a) is a plan view; FIG. 1(b) is an exploded perspective view; fig. 1(c) is a bottom view.

Fig. 2 shows a process of connecting the shunt resistor shown in fig. 1 to the case through the mounting wiring board.

Fig. 3 is a continuation of fig. 2.

FIG. 4 is a sectional view taken along line Ia-Ib in FIG. 3 (d).

Fig. 5 shows a fixing structure of a shunt resistor according to a second embodiment of the present invention.

FIG. 6 is a sectional view of the final fixing structure taken along the line Ia-Ib in FIG. 5 (c).

Fig. 7 shows a fixing structure of a shunt resistor according to a third embodiment of the present invention.

FIG. 8 is a sectional view of the final fixing structure taken along the line Ia-Ib in FIG. 7 (c).

Fig. 9 shows a fixing structure of a shunt resistor according to a fourth embodiment of the present invention, in which fig. 9(a) is an exploded perspective view, and fig. 9(b) is a perspective view in a screw state.

FIG. 10 is a sectional view of the final fixing structure taken along the line Ia-Ib in FIG. 9 (b).

Fig. 11 is a perspective view of another exemplary structure of a shunt resistor according to the fifth embodiment.

Fig. 12 is a state in which any one of the shunt resistors shown in fig. 11 is mounted on a case.

FIG. 13 is a sectional view of the final fixing structure taken along the line Ia-Ib in FIG. 12 (c).

Fig. 14 shows another example of the method of assembling the shunt resistor according to the first embodiment in the sixth embodiment of the present invention.

Fig. 15 shows another example of an assembling method of the shunt resistor according to the first and sixth embodiments in the seventh embodiment of the present invention.

Fig. 16 shows an example of a manufacturing process of the shunt resistor according to the first and sixth embodiments of the eighth embodiment of the present invention.

Fig. 17 shows an example of a mass production process of the shunt resistor shown in fig. 11(c) according to the ninth embodiment of the present invention.

Detailed Description

Hereinafter, a mounting structure of a shunt resistor and a current detection device using the shunt resistor according to an embodiment of the present invention will be described in detail with reference to the drawings.

First embodiment

First, a first embodiment of the present invention will be described.

The shunt resistor a of the present embodiment is made of a conductive metal material such as copper, and includes: a first terminal (electrode) 1 having a first plane 11a, a second plane 11b opposite to the first plane, and an outer peripheral surface (side surface) 11c surrounding the planes; and a second terminal (electrode) 3 made of a conductive metal material such as copper and having a first plane 13a, a second plane 13b, and an outer peripheral surface (side surface) 13c surrounding the two planes.

Openings (through holes) 1a, 3a penetrating from the first plane 11a, 13a to the

second plane

11b, 13b are formed in the first terminal 1 and the second terminal 3, respectively. Wherein, 1a is called the first through hole, and 3a is called the second through hole. In order to allow the following screws to penetrate the openings (through holes) 1a, 3a, the two openings are formed almost on the same axis.

The first planes 11a, 13a of the first terminal 1 and the second terminal 3, respectively, are opposed to each other, and a plurality of resistors 5 connected in parallel to the first terminal 1 and the second terminal 3 are provided on the two first planes 11a, 13 a. The resistor 5 can be made of copper-nickel series, copper-manganese series or nickel-chromium series metal materials. The top surface 5a and the bottom surface 5b of the resistor 5 are connected to the first planes 11a, 13a, respectively.

The total bonding area of the top surface 5a and the bottom surface 5b of the resistor 5 to the first planes 11a, 13a, respectively, is smaller than the area of the first planes 11a, 13 a. That is, as shown in fig. 1(a) and 1(c), the plurality of resistors 5 are fixed, for example, by welding, on the joining

regions

11d, 11d … …, 13d, 13d … … where the first plane 11a and the second plane 13b are joined to the plurality of resistors 5, respectively. Further, the fixing may be performed by soldering or the like. In the present embodiment, the plurality of resistors 5 are arranged in concentric circles with the

openings

1a, 3a formed in the first terminal 1 and the second terminal 3, respectively, as centers, for example, at equal intervals in the circumferential direction.

Further, a convex bump structure 6 is provided on the side of at least one of the first terminal 1 and the second terminal 3 (illustrated as the second terminal 3) opposite to the junction of the resistor 5.

The projection structure 6 is, for example, a ring-shaped structure having a through hole 6a at the center. The bump structures 6 may be made of a material such as copper having good conductivity, as well as the electrodes. The bump structure 6 may be, for example, either formed integrally with the second terminal 3 or attached thereto after being manufactured as a separate component. Furthermore, the first terminal 1 and the second terminal 3 may be provided with the bump structure 6 at the same time.

Hereinafter, an assembling method of the shunt resistor a will be briefly described. First, a first terminal 1, a second terminal 3 and a resistor (e.g., a cylindrical resistor) 5 are provided. Then, the resistor 5 is connected between the first terminal 1 and the second terminal 3, for example, by soldering, thereby forming a structure in which the first planes 11a, 13a of the first terminal 1 and the second terminal 3, respectively, are opposed to each other and the resistor 5 is connected between the first planes 11a, 13 a.

The resistance of the shunt resistor a can be adjusted by parameters such as the number, thickness and distance between the first terminal 1 and the second terminal 3 of the resistor 5.

Wiring devices such as bus bars can be connected to the

second planes

11b, 13b of the first terminal 1 and the second terminal 3, which are respectively located at the outer sides. In this way, a connection area necessary for a large current can be secured on the

second planes

11b, 13 b.

On the other hand, by making the resistor 5, for example, in a cylindrical shape and bonding with a bonding area smaller than the area of the first planes 11a, 13a, it is possible to prevent the resistance value of the shunt resistor from being excessively low, easily achieve resistance value design, and contribute to reducing the height of the shunt resistor.

Further, by arranging a plurality of resistors in concentric circles around the openings (through holes) 1a, 3a formed in the first terminal 1 and the second terminal 3, respectively, as centers, it is possible to not only make the shunt resistor a have a stable mechanical structure as a whole, but also contribute to making it have a detection accuracy that is stable under frequency variations.

The first terminal 1 and the second terminal 3 may be polygonal such as triangular or circular, in addition to being quadrangular. The

openings

1a and 3a may be polygonal, such as quadrangular, in addition to circular. Other embodiments are the same as above.

Fig. 2 shows a process of forming a current detection device by connecting the shunt resistor a shown in fig. 1 to the housing 81 via the wiring board (also referred to as "mounting board") 41. The mounting board 41 is provided with a circuit and various electronic components, and is provided with an integrated circuit or the like that performs current signal processing through the shunt resistor a. The case 81 is a housing or the like that accommodates therein a power module or the like containing a power semiconductor or the like.

As shown in fig. 2(a) and 2(b), the second wiring structure 51 is formed on the housing 81. The mounting wiring board 41 is mounted on the second wiring structure 51. The mounting board 41 is formed with through holes 41c, hereinafter referred to as third through holes, having an inner diameter approximately equal to the outer diameter of the boss structure 6. The through hole 41c is disposed opposite to the through hole 51a formed in the second wiring structure 51. Voltage detection terminal connection through

holes

41a, 41b for connecting voltage detection terminals of the shunt resistors are also provided in the mounting board 41.

As shown in fig. 2(b), in a state where the mounting wiring board 41 is mounted on the housing 81, the projection structure 6 of the shunt resistor a is accommodated in the through hole 41c, and the first and second

voltage detection terminals

61a, 61b are formed on the first terminal 1 and the second terminal 3, respectively. One ends of the first and second

voltage detection terminals

61a, 61b are fixed to the first terminal side surface 11c and the second terminal side surface 13c, respectively. The other ends of the first and second voltage detection terminals are inserted into through

holes

41a, 41b formed in the mounting board 41, respectively, and then fixed by soldering.

The bottom surface of the projection structure 6 abuts against the top surface of the second wiring structure 51 while the projection structure 6 is fitted into and accommodated in the through hole 41c, so that the shunt resistor a can be temporarily fixed to the mounting wiring board 41.

For example, by setting the thickness of the bump structure 6 to be equal to the thickness of the mounting wiring board 41, the bottom surface of the bump structure 6 can be made to abut against the top surface of the second wiring structure 51, thereby conducting the second terminal 3 to the second wiring structure 51. Further, by making the bottom surface (S1 in fig. 4) of the second terminal 3 abut against the top surface portion (four corner regions) of the mounting wiring board 41, an effect of pressing the shunt resistor a against the mounting wiring board 41 can be produced.

Fig. 3(c) is an exploded perspective view of the temporarily fixed shunt resistor a and the mounting board 41 completely fixed to the case 81. FIG. 3(d) is a perspective view showing a state after screwing. FIG. 4 is a sectional view taken along line Ia-Ib in FIG. 3 (d).

The shunt resistor a and the mounting wiring board 41 temporarily fixed are screwed to the case 81 through the through-hole 71a formed in the bus bar 71, the first through-hole 1a and the second through-hole 3a formed in the first terminal 1 and the second terminal 3 of the shunt resistor a, the third through-hole 41c formed in the mounting wiring board 41, the through-hole 51a formed in the second wiring structure 51, and the screw 101, and through the insulating member 91 having an electrical insulating property. A nut 87 is provided on one side of the housing 81 as a receiving end for a screw 101. Since the second terminal 3 is pressed to cover a part of the mounting wiring board 41 from the top down, it functions to position the mounting wiring board 41 and the shunt resistor a. In this way, particularly when the components such as the circuit board 41 are mounted, it is possible to prevent generation of an excessive load which may break the connection portions between the

voltage detection terminals

61a, 61b and the voltage detection terminal connection through

holes

41a, 41 b.

The insulating member 91 includes a flat plate-like head portion 93 and a cylindrical portion 95 in contact with the head portion. The flat plate-like head 93 insulates the screw 103 from the surface of the bus bar 71, and the cylindrical portion 95 is internally provided for insertion of the rod portion 105 of the screw 101, thereby insulating the outer peripheral surface of the rod portion 105 from the bus bar 71 and the side surface of the first terminal 1. Thus, the insulating state between the terminals can be maintained. Further, the thickness of the shaft portion 105 of the screw 101 and the inner diameter of the through-hole 3a are set so that the inner surface of the through-hole 3a of the second terminal 3 does not contact the outer peripheral surface of the screw 101.

That is, the second terminal 3 and the second wiring structure 51 are connected through the through hole 41c formed in the mounting wiring board 41.

Since the inner surface of the through hole 41c is engaged with the outer peripheral surface of the projection structure 6 along the entire circumference, the horizontal movement of the shunt resistor a can be restricted, thereby surely achieving the fixation of the shunt resistor a in the horizontal direction. Further, in the fixing structure of fig. 4, since the bottom surface of the second terminal 3 abuts against the top surface portion of the mounting wiring board 41 in the region other than the projection structure 6, the fixing of the shunt resistor a and the mounting wiring board 41 in the vertical direction is made more firm with the fixing of the screws 101. That is, since the upper and lower sides of the shunt resistor a are fixed by being pressed, the fixing structure is more firm.

In this way, in the fixing structure of the current detection device, the connection of the shunt resistor a and the mounting board 41 to the case 81 can be made more firm.

Second embodiment

Hereinafter, a second embodiment of the present invention will be described. Fig. 5 shows a fixing structure of the shunt resistor according to the present embodiment, in which fig. 5(a) corresponds to fig. 2(a), fig. 5(b) corresponds to fig. 2(b), and fig. 5(c) corresponds to fig. 3(c) (the screw 101 is omitted).

The mounting wiring board 41 is provided with a through hole 41d for the second wiring structure 51 provided on the housing. In the present embodiment, the opening of the through hole 41d is sufficiently large compared to the second terminal 3. As shown in fig. 5(a) and 5(b), the mounting wiring board 41 is disposed such that the through-hole 41d is opposed to the second wiring structure 51. The mounting wiring board 41 is placed on the spacer 122 and fixed to the housing 81 by screws 122 a. At this time, the second wiring structure 51 does not contact the mounting wiring board 41. Subsequently, as shown in fig. 5(b) and 5(c), the shunt resistor a is mounted so as to be accommodated in a through hole 41d formed in the mounting wiring board 41. Wherein the second terminal 3 is connected to the second wiring structure 51, and the mounting wiring board 41 is separated from the second terminal 3 and the second wiring structure 51. The

voltage terminals

61a, 61b are inserted into the voltage detection terminal connection through

holes

41a, 41b of the mounting wiring board 41, and connection is effected.

Fig. 6 is a sectional view taken along line Ia-Ib after the screw 101 is passed through the through hole formed in the electrode 1, 3 and fastened to the nut 87 on the side of the case in the state shown in fig. 5 (c). Wherein the through hole 41d is sized so that the shunt resistor a does not contact the mounting wiring board 41 except for the

voltage detection terminals

61a, 61 b. Although the shunt resistor a generates heat during use, with the structure of the present embodiment, the transfer of the amount of heat generated by the shunt resistor a to the mounting circuit board 41 can be suppressed.

Third embodiment

Hereinafter, a third embodiment of the present invention will be described. Fig. 7 shows a fixing structure of a shunt resistor a according to the present embodiment, in which fig. 7(a) corresponds to fig. 2(a) of the first embodiment, fig. 7(b) corresponds to fig. 2(b) of the second embodiment, and fig. 7(c) corresponds to fig. 3(c) of the second embodiment.

In the present embodiment, a ring-shaped fixing member 85 is provided on the top surface of the second wiring structure 51 provided on the housing 81. The second wiring structure 51 including the ring-shaped fixing member 85 is provided with a through hole 85 a. The through hole 41c of the mounting board 41 has a size and a shape into which the annular fixing member 85 is fitted.

When the mounting board 41 is set on the housing 81, the annular fixing member 85 is fitted into the through hole 41c of the mounting board 41. Preferably, in this state, the mounting wiring board 41 is flush with the fixing member 85.

Further, the shunt resistor a is mounted on the mounting circuit board 41. In this state, as shown in fig. 8, the shunt resistor a and the mounting board 41 may be fixed to the case 81 by screws 101 or the like. As for the insulating structure formed by the insulating member 91, it is the same as the first embodiment described above with reference to fig. 3 and 4.

The peripheral edge portion of the bottom surface of the second terminal 3 abuts against the peripheral edge of the through hole 41c of the mounting wiring board 41 (the abutting surface is denoted by reference numeral S), thereby exerting a pressing action on the mounting wiring board 41.

According to the present embodiment, the shunt resistor a can be stably mounted thereon in a state where the mounting wiring board 41 and the fixing member 85 are fixed.

Fourth embodiment

Hereinafter, a fourth embodiment of the present invention will be described. Fig. 9 shows a fixing structure of the shunt resistor according to the present embodiment, in which fig. 9(a) is an exploded perspective view, and fig. 9(b) is a perspective view in a screw state. Fig. 10 shows a structure after screwing, which differs from fig. 4 in the following points:

a nut 87 is arranged below the bus bar 73, and the shunt resistor is clamped between the first bus bar 71 and the second bus bar 73 and is screwed by a screw 101;

(II) the

voltage detection terminals

61a, 61b respectively extending from the first terminal 1 and the second terminal 3 are inserted and fixed into the voltage detection terminal connection through

holes

41a, 41b of the mounting wiring board 41 after passing through the terminal reinforcing member (cushion material) 82 made of an elastic body.

In the present embodiment, the shunt resistor a and the mounting board 41 are fixed by the

voltage detection terminals

61a, 61 b.

Further, by interposing the elastic body terminal reinforcing member 82 between the shunt resistor a and the mounting circuit board 41, the strength of the

voltage detection terminals

61a, 61b can be increased.

Fifth embodiment

Hereinafter, a fifth embodiment of the present invention will be described. Fig. 11(a) to 11(c) are oblique views of other examples of the shunt resistor according to the present embodiment. The shunt resistor a1 shown in fig. 11(a) includes a resistor 153 and first and second electrodes (terminals) 151a, 151 b. Wherein the electrodes are bent such that the resistor has a U-shaped (C-shaped) cross-section. In the shunt resistor a2 shown in fig. 11(b), the resistor 153a and the

electrodes

151a, 151b are connected at the end face of the resistor 153a and the surface or the back of the end of the electrode. In the shunt resistor A3 shown in fig. 11(c), in addition to the shunt resistor a2 shown in fig. 11(b), one resistor 153a, that is, two resistors 153a are provided on the end portions of the

electrodes

151a, 151b on the side opposite to the resistor 153 a.

In the shunt resistors a1 to A3, through

holes

155a, 155c are provided in the vertically corresponding portions of the first and

second electrodes

151a, 151 b. Further, voltage detection terminals 157a, 157b are provided on portions of the first and

second electrodes

151a, 151b adjacent to the

resistors

153, 153a, respectively, and extend outward from the surfaces of the

resistors

153, 153a in a direction perpendicular to the surfaces.

Fig. 12 shows a state where the shunt resistor a2 is mounted on the case 81. As shown in fig. 12(a), a spacer 121 having a through hole 121a is provided between the

electrodes

151a, 151b, and a shunt resistor a2 is mounted on the wiring structure 51 on the case 81. Specifically, since one end of the electrode is open in the shunt structures of a1 and a2, there is a problem that deformation is likely to occur by a pressure such as screwing. The spacer 121 (made of an electrically insulating material such as ceramic or rubber) is provided to prevent deformation during screwing.

Subsequently, as shown in fig. 12(b) and 12(c), the shunt resistor a2 and the bus bar 71 provided thereon are fixed by the screw 101 and the insulating member 91. As for the insulating structure formed by the insulating member 91, it is the same as the first embodiment described above with reference to fig. 3 and 4.

In this manner, as shown in fig. 13, the shunt resistor a2 can be fixed to the case 81 by the spacer 121 by the screw 101.

This embodiment has an advantage that deformation is not likely to occur at the time of screwing.

In addition to the above-described screwing action, the spacers 121 also have an advantage of being able to increase the strength of the flow dividing structure shown by a1 or a 2.

Sixth embodiment

Hereinafter, a sixth embodiment of the present invention will be described.

Fig. 14 shows an example of an assembling method of the shunt resistor a according to the first embodiment.

As shown in fig. 14(a), first, the second terminal 3 having the bump structure 6 is provided. Then, as shown in fig. 14(b), four pieces of T-shaped holders 201a to 201d are stacked on the second terminal 3. In the case where the resistor 5 is four, in order to achieve positioning of the resistor 5, four pieces of T-shaped brackets 201a to 201d are stacked such that the upper half of the T-shape thereof coincides with the four sides of the second terminal 3. Semicircular cutouts 202 are provided on both sides of the upper half of the T-shape.

By superimposing the four cutouts 202, the inner surfaces of the four temporary fixing holes 203 (resistor predetermined setting positions) holding the four resistors 5 in predetermined positions can be formed.

Subsequently, as shown in fig. 14(c), four resistors 5 are respectively disposed in the four temporary fixing openings 203, and the second terminals 3 are fixed to the four resistors 5 by a fixing method based on soldering or by a fixing method based on an adhesive (a nano paste or the like containing nanoparticles of an element such as copper or silver may be used). Thereafter, as shown in fig. 14(d), the first terminal 1 and the four resistors 5 are fixed by a fixing method by soldering or a fixing method by an adhesive. As shown in fig. 14(e), the four holders 201a to 201d are removed, and then the shunt resistor a is formed.

According to the present embodiment, the resistor can be easily positioned by using the detachable positioning tool.

Seventh embodiment

Hereinafter, a seventh embodiment of the present invention will be described.

Fig. 15 shows another example of an assembling method of the shunt resistor a according to the first and sixth embodiments. As shown in fig. 15(a), first, a positioning tool 301 is provided. The positioning fixture 301 includes, for example, a square bottom plate 301a and side walls 301b erected from four sides thereof so as to form a receiving space S for receiving the second terminal 3. Further, a plurality of grooves (slots) 301c are formed in the upper half portion of the side wall 301 b. In fig. 15(a), four concave grooves 301c are formed in each side wall 301 b.

As shown in fig. 15(b), the second terminal 3 is set in the receiving space S of the positioning fixture 301 so that the top surface of the bottom plate 301a abuts against the bottom surface of the second terminal 3. Subsequently, as shown in fig. 15(c), an elastic thread 303a is passed into each pair of the opposing grooves 301 c. In fig. 15(c), four elastic threads 303a are fed in one direction, and four elastic threads 303a are fed in a direction perpendicular to the one direction, for a total of eight elastic threads 303 a. In this way, the elastic threads 303a form a3 × 3 substantially square lattice (9 squares in total).

In these 9 squares, the cylindrical resistors 5 can be arranged, for example, upright in the respective square in the desired position. As shown in fig. 15(d), when the adjacent resistors 5 are spaced apart by a space of one square, short circuit between the resistors 5 can be prevented. In the case shown, four resistors 5 are provided standing together.

As shown in fig. 15(e), four resistors 5 are placed on and connected to the first terminal 1.

As shown in fig. 15(f), the positioning tool 301 is removed after the elastic wire 303a is removed, so that a shunt resistor can be formed as in the case shown in fig. 1.

According to the present embodiment, with the groove (slot) 301c and the elastic wire 303a on the positioning jig 301, the resistor 5 can be disposed at a desired position between the first terminal 1 and the second terminal 3, and the degree of freedom in the arrangement shape and the number of arrangements of the resistor can be improved. Secondly, because only need let in the elastic thread can, consequently still can reduce the required cost of equipment. Third, this embodiment also has the advantage that the elastic wire is easily removed after the resistor is fixed.

Eighth embodiment

Hereinafter, an eighth embodiment of the present invention will be described.

Fig. 16 shows an example of a part of the manufacturing process of the shunt resistor a according to the first and sixth embodiments.

As shown in fig. 16(a), first, a resin, such as epoxy resin 5x, is applied to the outer surface of the elongated resistive material, and then hardened.

The resistive material is then cut to the desired length to form individual resistors 5.

As shown in the side view of fig. 16(b), the resistor 5 is disposed between the first terminal 1 and the second terminal 3. The second terminal 3 may be provided with the projection structure 6 described in the first embodiment.

According to the present embodiment, since the insulating coating is formed on the outer surface of the resistor 5, for example, in the seventh embodiment, even when the resistors 5 are disposed in adjacent positions, short-circuiting between the resistors 5 can be prevented, thereby improving the degree of freedom in the disposition of the resistors 5.

Further, in the case where the resistor 5 is connected to the first terminal 1 and the second terminal 3 by soldering, fluctuation in resistance value due to tin-climbing can also be alleviated.

Ninth embodiment

Hereinafter, a ninth embodiment of the present invention will be described.

Fig. 17 shows an example of a mass production process of the shunt resistor shown in fig. 11 (c). As shown in fig. 17(a), first terminal material 151a and second terminal material 151b are first brought into an opposed state, and then first resistive material 153a and second resistive material 153b opposed to each other are disposed therebetween, thereby forming a substantially rectangular parallelepiped structure as shown in fig. 17 (b).

As shown in fig. 17(c), a plurality of through

holes

155a, 155c are formed at opposite positions of the first terminal material 151a and the second terminal material 151b, respectively.

As shown in fig. 17(d), by cutting at a predetermined position, each shunt resistor is formed. Subsequently, as shown in fig. 17(e), the

voltage detection terminals

107a, 107b are provided on the end surfaces of the first terminal 151a and the second terminal 151b by soldering or the like.

By the above steps, mass production of the shunt resistor shown in fig. 11(c) can be realized.

The above-described embodiments are not limited to the various configurations shown in the drawings, and may be appropriately modified within a range in which the effects of the present invention can be achieved. The present invention can be carried out with appropriate modifications without departing from the scope of the object of the present invention.

In addition, each component of the present invention may be arbitrarily selected or substituted, and all inventions having a structure obtained by such selection or substitution are also encompassed in the present invention.

Industrial applicability

The invention can be used for shunt resistors.

Reference numerals

A shunt resistor

1 first terminal (electrode)

1a open pore (first through hole)

3a open pore (second through hole)

3 second terminal (electrode)

5 resistor

6 protruding structure

41 mounting wiring board (Wiring board)

41a Voltage detection terminal connection Via

41b Voltage detection terminal connection Via

41c third through hole

61a first voltage detection terminal

61b second voltage detection terminal

71 bus bar

81 casing

85 fixed component

91 insulating member

103 screw

All publications, patents and patent applications cited in this specification are herein incorporated in their entirety by this reference.

Claims

1. A current detecting device, comprising:

a first wiring structure and a second wiring structure forming a current path;

a housing provided with the second wiring structure;

a circuit board; and

a shunt resistor shorting the first and second wiring structures, the shunt resistor comprising: a first terminal and a second terminal made of a conductive metal material; and a plurality of columnar resistors provided between the first terminal and the second terminal, wherein the first terminal and the second terminal are formed with a first through hole and a second through hole, respectively, and the second terminal is formed with a bump structure, wherein the bump structure is a ring structure,

in the shunt resistor:

the first terminal is connected with the first wiring structure;

the second terminal is connected with the second wiring structure through a third through hole formed in the circuit board;

the shunt resistor and the second wiring structure are fixed by fixing members inserted in the first through hole and the second through hole,

the resistor is connected in parallel between the first terminal and the second terminal,

the protruding structure is accommodated in the third through hole.

2. The current detection device of claim 1,

and the second terminal presses against the peripheral part of the third through hole of the circuit board.